Role of great artery annulus ratio to predict transannular patch enlargement in repair of tetralogy of Fallot

Abstract
Background
Traditionally, the pulmonary valve annulus (PVA) z-score is used to predict the requirement of transannular patch enlargement (TAPE) of right ventricular outflow tract (RVOT) and main pulmonary artery (MPA) in repair of tetralogy of Fallot (TOF). PVA z-score is highly variable and many other parameters are being reported to be accurate in predicting need of TAPE. In this study, we analyze the role of great artery annulus ratio (pulmonary valve annulus to aortic valve annulus ratio, PVA/AVA) to be used as a predictor for TAPE.

Methods
We analyzed 90 patients of TOF retrospectively who underwent repair between January 2021 and December 2021. The patients were divided as TAPE group who required TAPE of RVOT and MPA and non-TAPE group who did not have TAPE. Their baseline parameters, PVA Z-score, and cut-off great artery annulus ratio were compared.

Results
Total 44 (48.9%) patients had transannular patch (TAPE) repair and 46 (51.1%) patients had non-transannular patch repair. The great artery annulus ratio and PVA z-score was lower in case of TAPE group with statistical significance. Receiver operating characteristic curve analysis showed great artery annulus ratio as more accurate predictor of TAPE.

Conclusion
Great artery annulus ratio can be used as a simple and accurate predictor for transannular patch enlargement along with PVA z-score during repair of TOF.